This control has a dual voltage switch allowing the control to be used on 115 or 230 volt, single phase, 50/60 Hertz service. However, the proper voltage motor should be selected for use with the power supply input, i.e., 90 volt DC motors for 115 volt input or 180 volt motors for 230 volt input service. Installation and adjustment instructions are included. Chassis Heat Sink # 174314.00 required when the amp draw of the motor exceeds 5 amps. Recommended for 3/4 and 1HP using 115V input and 1 1/2 and 2HP using 230V input.